The present article is devoted to research in genesis and evolution of views of medieval thinker Ahmad b. al-Ha’it (d. 847). Being a unique fi gure for his time, Ibn al-Ha’it played a signifi cant role in the formation of Arabic philosophy, which, unfortunately, is ignored to this day by specialists-medievalists: so, for the fi rst time in the history of intellectual thought of the medieval Middle East, the Mu’tazilli philosopher made an attempt of an exit from a strict theologism of Kalam to the tradition, which was issued in Falsafah. Justifi cation of the reincarnation theory within the Islamic theological fi eld which is initially constructed on postulates of singularity and an extremity of any terrestrial human life became a separate merit of Ahmad. Along with it, the thinker attracted the arianistic doctrine, which allowed by him to develop his own Christology and ontology in neoplatonic paradigmatics. Thereby, the pupil of a great Basrian thinker Ibrahim b. Sayyar an-Nazzam anticipated the great synthesis of Kalam and Arabic peripatetizm realized by late Ash’arites - al-Ghazali (d. 505/1111), Fakhruddin ar-Razi (d. 606/1210) and ʻUdud ad-Din al-Iji (d. 756/1355).